#!/usr/bin/env python
# Copyright (c) Facebook, Inc. and its affiliates.
# All rights reserved.
#
# This source code is licensed under the license found in the
# https://github.com/pytorch/fairseq/blob/master/LICENSE


import argparse
import sys

import sentencepiece as spm


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("--model", required=True,
                        help="sentencepiece model to use for decoding")
    parser.add_argument("--input", default=None, help="input file to decode")
    parser.add_argument("--input_format", choices=["piece", "id"], default="piece")
    args = parser.parse_args()

    sp = spm.SentencePieceProcessor()
    sp.Load(args.model)

    if args.input_format == "piece":
        def decode(l):
            return "".join(sp.DecodePieces(l))
    elif args.input_format == "id":
        def decode(l):
            return "".join(sp.DecodeIds(l))
    else:
        raise NotImplementedError

    def tok2int(tok):
        # remap reference-side <unk> (represented as <<unk>>) to 0
        return int(tok) if tok != "<<unk>>" else 0

    if args.input is None:
        h = sys.stdin
    else:
        h = open(args.input, "r", encoding="utf-8")
    for line in h:
        print(decode(line.split()))


if __name__ == "__main__":
    main()
